https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3850/software/release/16-3/configuration_guide/b_163_consolidated_3850_cg/b_163_consolidated_3850_cg_chapter_01001011.html
https://www.youtube.com/watch?v=GxRdPPsIHH8&t=1186s
Identifier (Entity ID) URL: https://vpn.domain.com:443/SAML20/SP
The 443 is needed
Reply URL (Assertion Consumer Service URL): https://vpn.domain.com:443/SAML20/SP/ACS